Who Is Christian Pulisic? 20-year-old Signs with Chelsea to Become Most Expensive U.S. Soccer Player Ever

Christian Pulisic has become the most expensive soccer player in American history after completing a $73 million move to Chelsea.

On Wednesday, Chelsea confirmed it had reached an agreement with German club Borussia Dortmund for the 20-year-old.

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Pulisic will remain on loan to his current club until the end of the campaign before moving to the Premier League in the summer.

Speaking with Chelsea's official website, Pulisic said it was "a privilege to have signed for such a legendary club and I look forward to working hard towards being a contributor to their team of world class players".

He then posted a statement on Twitter, emphasizing that while he was excited at the prospect of joining the English club, Dortmund would remain his main focus until the end of the season.

"For the next six months, it's all BVB [Borussia Dortmund]," he tweeted.

"Please do not doubt my passion, determination and my 110% commitment to the team, right until the last ball is kicked this season. We all feel that this is 'our year' and we are determined to achieve the best possible results in all competitions."

Pulisic has only won the German Cup since joining the German club in 2016 but has the opportunity to add a league title this season, as Dortmund lead the Bundesliga by six points at the halfway mark of the campaign.

Chelsea are currently fourh in the Premier League and could move within two points of second-placed Tottenham Hotspur if they beat Southampton at home on Wednesday.

Born in Hershey, Pennsylvania, Pulisic moved to Germany as a teenager, rapidly progressing through Dortmund's youth ranks to make his first team debut aged just 17.

He has since made 115 senior appearances for the club, scoring 15 goals in all competitions, but has failed to nail down a spot in the starting line-up this season.

In the current campaign, Pulisic has only started five league games and made six further appearance as a substitute, as opposed to last season when he made 27 Bundesliga starts and came on as a substitute five times.

Ironically, Pulisic's chances have been limited by the emergence of 18-year-old Jadon Sancho, who left Manchester City in 2017 after being frustrated at the lack of first-team opportunities.

Pulisic's move to Chelsea will not be his first foray in England, where he spent a year as a seven-year-old.

He then returned to the U.S. with his parents—both of whom played college soccer at George Mason University—as his father took charge of indoor club Detroit Ignition.

As the family moved back to Pennsylvania, Pulisic played for PA Classics, the local U.S. Soccer Development Academy.

Following his move to Dortmund, the 20-year-old sensation became a Croatian citizen to avoid having to apply for a work visa in Germany.

Pulisic was eligible for Croatian citizenship as his grandfather, Mate, was born in Croatia. In 2016, the new Chelsea signing received an offer to represent the country of birth of his grandfather but turned it down.

He made his U.S. National Team debut in May of the same year and has since scored nine goals in 23 appearances, becoming the youngest player to captain the team when he led the U.S. out against Italy in November.